How to use switchMap to handle dependent HTTP requests in RxJS

Question

With the help of code can you tell me How to use switchMap to handle dependent HTTP requests in RxJS?

Answer 1

Using switchMap for Dependent HTTP Requests in RxJS

The switchMap operator is ideal for handling dependent HTTP requests where you need to:

Make an initial request

Use its response to make a subsequent request

Cancel the previous inner observable if a new outer value arrives

Basic Usage

import { switchMap } from 'rxjs/operators';

import { from } from 'rxjs';

firstRequest().pipe(

  switchMap(firstResponse => {

    return secondRequest(firstResponse.id);

  })

).subscribe(secondResponse => {

});